Which of these is a major difference between smooth muscle and skeletal muscle?
A. Only skeletal muscle requires increased calcium ion concentration in the cytosol for contraction.
B. Only skeletal muscle has both actin and myosin.
C. Myosin is the main regulatory protein in smooth muscle.
D. Myosin is the main regulatory protein in skeletal muscle.
E. Skeletal muscle usually exhibits spontaneous activity, while smooth muscle cannot contract spontaneously.
Answer: C
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____________________ refers collectively to the large set of intracellular chemical reactions that involve the degradation, synthesis, and transformation of small organic molecules
Fill in the blank(s) with correct word
Which of the following is true regarding joints that are first-class levers?
A. The joint (fulcrum) is at the opposite end from the tendinous attachment (effort). B. Their resistance is between the joint (fulcrum) and the distal end of the bone (effort). C. Their mechanical advantage is always less than 1.0. D. Their mechanical advantage may be either greater or less than 1.0. E. Their output force is always greater than the input force.
During which event of the cardiac cycle do the atria both relax and contract?
a. Isovolumetric relaxation b. Ventricular filling c. Isovolumetric contraction d. Ventricular ejection
Turning the ankle so that the plantar surface faces laterally is
A. eversion. B. inversion. C. supination. D. retraction.